Direct application of biota-sediment accumulation factors

In the early stages of risk assessments for sites with contaminated sediments, predictions of risks are often complicated or limited by sparse or inadequate bioaccumulation data. These limitations often require risk assessors to estimate bioaccumulation relationships in order to complete the assessments of risk. In the present study, the errors are evaluated with the simple (direct) application of field measured biota-sediment accumulation factors (BSAFs) to other species at a specific location, and to the same species and/or other species at other locations within a site and to other sites. The median (90th percentile) differences in directly applying BSAFs to other species at a specific location were < or =2.1x (< or =5.1x) for fish and mussel species groups. The median (90th percentile) differences for applications across locations within a site for a specific species and to other species were < or =3.3x (< or =10x) for fish, mussel, and decapod crustacean groups. For direct application across sites, slightly larger median (90th percentile) differences were observed, i.e., < or =4.0x (< or =12x). The analysis was performed using a data set of 17,848 BSAFs spanning 392 chemicals/chemical combinations and 71 species.